Tape measure having a laser transmission window

Abstract

A tape measure to be reeled on a spool rotatably mounted within a housing defining an opening for paying out and for retrieval by rotation of the spool within in the housing. The tape measure includes a tape having a first end and a second end. The first end connected to the spool and the second end movable through the opening between a retracted position and an extended position. The tape includes a steel blade with length markings on the obverse. The blade extends along its length from the first end to the second end having a window. The window includes a pane of polymer. The polymer includes pigments to selectively transmit laser emitted from a laser level. The pane in held within the window in a manner allowing the reel to pay out and retract the blade in use.

The invention claimed is: 
     
       1. A tape measure to be reeled on a spool rotatably mounted within a housing defining an opening for paying out and for retrieval by rotation of the spool within in the housing, the tape measure comprising:
 a tape including a first end and a second end, the first end connected to the spool and the second end movable through the opening between a retracted position and an extended position, the tape comprising:
 a steel blade with length markings on the obverse, the blade extending along its length from the first end to the second end and defining a window therein, the window being defined to extend parallel to the length; and 
 a pane of polymer, the polymer including pigments to selectively transmit laser emitted from a laser level, the pane being held within the window in a manner allowing the reel to pay out and retract the blade in use. 
 
 
     
     
       2. The tape measure of  claim 1 , wherein the steel blade defines the window as extending within only that part of the blade extending along its length approximately twelve inches from first end. 
     
     
       3. The tape measure of  claim 2 , wherein the steel blade defines the window as extending within only that part of the blade extending along its length from a position proximate to the 3½ inch marking to the 7½ inch marking. 
     
     
       4. The tape measure of  claim 1 , wherein the pane of polymer is selected to transmit laser light at a wavelength selected from a range from violet at 400 nm to red at 700 nm. 
     
     
       5. The tape measure of  claim 4 , wherein the pane of polymer is selected to transmit laser light from a group of laser light wavelengths consisting of red (630 nm to 670 nm), green (520 nm to 532 nm) and violet (405 nm to 445 nm). 
     
     
       6. A method for measuring an offset between an architectural feature, the method comprising:
 providing a tape including a first end and a second end, the first end connected to the spool and the second end movable through the opening between a retracted position and an extended position, the tape comprising:
 a steel blade with length markings on the obverse, the blade extending along its length from the first end to the second end and defining a window therein, the window being defined to extend parallel to the length; and 
 a pane of polymer, the polymer including pigments to selectively transmit laser emitted from a laser level, the pane being held within the window in a manner allowing the reel to pay out and retract the blade in use; 
 
 placing a laser level relative to the architectural feature, the laser lever emitting a true vertical laser beam; 
 placing the tape such that the true vertical laser beam such that its first end abuts the architectural feature at a first measurement point and the laser beam intersects the tape at the pane of polymer to produce an illuminated laser spot therein; and 
 reading a first length marking proximate to the laser spot. 
 
     
     
       7. The method of  claim 6 , wherein the steel blade defines the window as extending within only that part of the blade extending along its length approximately twelve inches from first end. 
     
     
       8. The method of  claim 7 , wherein the steel blade defines the window as extending within only that part of the blade extending along its length from a position proximate to the 3½ inch marking to the 7½ inch marking. 
     
     
       9. The method of  claim 6 , wherein the pane of polymer is selected to transmit laser light at a wavelength selected from a range from violet at 400 nm to red at 700 nm. 
     
     
       10. The method of  claim 9 , wherein the pane of polymer is selected to transmit laser light from a group of laser light wavelengths consisting of red (630 nm to 670 nm), green (520 nm to 532 nm) and violet (405 nm to 445 nm). 
     
     
       11. The method of  claim 6  further including:
 to determine plumbness of the architectural features, placing the tape such that the true vertical laser beam such that its first end abuts the architectural feature at a second measurement point vertically aligned with the first measurement point and the laser beam intersects the tape at the pane of polymer to produce an illuminated laser spot therein; and 
 reading a second length marking proximate to the laser spot. 
 
     
     
       12. The method of  claim 11  further including:
 to further determine plumbness of the architectural features, placing the tape such that the true vertical laser beam such that its first end abuts the architectural feature at a third measurement point vertically aligned with the first measurement point and second measurement point and the laser beam intersects the tape at the pane of polymer to produce an illuminated laser spot therein; and 
 reading a third length marking proximate to the laser spot. 
 
     
     
       13. A tape for use in a tape measure, the blade to be reeled on a spool rotatably mounted within a housing defining an opening for paying out and for retrieval by rotation of the spool within in the housing, the tape comprising:
 a steel blade including a first end and a second end, the first end configured for connection to the spool and the second end movable through the opening between a retracted position and an extended position, with length markings on the obverse, the blade extending along its length from the first end to the second end and defining a window therein, the window being defined to extend parallel to the length; and 
 a pane of polymer, the polymer including pigments to selectively transmit laser emitted from a laser level, the pane being held within the window in a manner allowing the reel to pay out and retract the blade in use. 
 
     
     
       14. The tape of  claim 13 , wherein the window the steel blade defines extending within only that part of the blade extending along its length to approximately twelve inches from first end. 
     
     
       15. The tape of  claim 14 , wherein the steel blade defines the window as extending within only that part of the blade extending along its length from a position proximate to the 3½ inch marking to the 7½ inch marking. 
     
     
       16. The tape of  claim 13 , wherein the pane of polymer is selected to transmit laser light at a wavelength selected from a range from violet at 400 nm to red at 700 nm. 
     
     
       17. The tape of  claim 16 , wherein the pane of polymer is selected to transmit laser light from a group of laser light wavelengths consisting of red (630 nm to 670 nm), green (520 nm to 532 nm) and violet (405 nm to 445 nm).